Air operated circuit breaker



Nov. 24, 1953 Filed Dec. 8. 1948 J. D. woon 2,660,635

AIR OFERATED CIRCUIT BREAKER 5 Sheets-Sheet l INVENTOR.

Qae/J/z D. blood. B Y

ATTORNEYS.

Nov.- 24, 1953 J. D. woon 2,660,635

AIR OPERATED CIRCUIT BREAKER Filed DeC. 8, 1948 5 Sheets-Sheet 2 82 161190 IIL/r 1 w1 F 19e R197 185 95 20o f g 185 3o 11 J 40 33 11 I L5 M q/j 2 A mvENToI.

m Qfl? @OMM Y @6M Nov. 24, 1953 J. D. wooD 2,660,635

AIR OPERATED CIRCUIT BREAKER Filed Dec. 8, 1948 5 Sheets-Sheet 5 4 1251.L 157 if 1g 3 141 215 191 176% Vw 15 216 V 175 6152155' 154 139 I 1'67 i17a 18o 17e m 181 65 n 12a 129 *I 140 H 8 M195 184 l 173 f: F' 19 197185 Oo 6 32 4o 55 "'11 5L J v INVENTOR. BY Qde/:a D. Jdozl ATTORNEYS.

Nov. 24, 1953 Filed Dec. 8, 1948 J. D. WOOD AIR OPERATED CIRCUIT BREAKER5 Sheets-Sheet 4 INVENTOR.

By Qca effi h/foaf (9W YW dtml/myd Nov. 24,' 1953 J. D. woon 2,660,635

AIR OPERATED CIRCUIT BREAKER Filed Dec. 8, 1948 5 Sheets-Sheet 5 INVENTOR.

ATTORNEYS.

Patented Nov. 24, 1953 AIR OPERATED lCIRCUIT BREAKER Joseph D. Wood,Strafford Village, Pa.,

to I-T-E Circuit Breaker Company,

assigner Philadelphia, Pa., a corporation of Pennsylvania ApplicationDecember 8, 1948, Serial No. 64,085 4 Claims. (Cl. ZOU-81.5)

My present invention relates to circuit breakers and more particularlyto a portable air operating system for use in connection with a circuitbreaker and especially for use in connection with a mult1- plicity ofcircuit breakers wherein the portable air operating system may beattached and detached to the particular circuit breaker which 1t isdesired to operate.

Primarily, my invention is directed to auxlhary means to close circuitbreakers if for any reason the mechanical or electrical operating meansfor closing the circuit breaker fails to operate.

If for any reason in the case of solenoid closing breakers the solenoidshould fail to operate, it is desirable and in many cases necessary toeliminate the need for an operator to close the breaker manually againsta possible short circuit.

My invention contemplates extending the guide tube for the solenoidplunger or armature downwardly in order to form a cylinder in which thesolenoid plunger or armature comprises the piston.

A connection is made to the end of the guide tube through a convenienttube or pipe to the opposite end of which a compressed air source mayreadily be attached when desired. Admission of compressed air into theguide tube will force the solenoid plunger up, thereby operating thecircuit breaker to the closed position.

Accordingly, the primary object of my invention is the provision ofnovel air operating means for a circuit breaker.

Another object of my invention is the provision of auxiliary airoperating means for a circuit breaker.

Another object of my invention is the provision of auxiliary operatingmeans for a circuit breaker utilizing the solenoid armature as a pistonand its guide tube as a cylinder in an auxiliary compressed air system.

Another object of my invention is the provision of novel air operatingmeans for a circuit breaker which may be made portable and movable fromcircuit breaker to circuit breaker in a switchboard or a multiplicity ofswitchboards.

The foregoing and many other objects of my invention will becomeapparent in the following description and drawings in which:

Figure 1 is a View in perspective showing the manner of use of my novelportable compressed air system.

Figure 2 is a schematic view showing the operation of my novel auxiliarycompressed air operating system in connection with a specific solenoidoperating circuit breaker.

Figure 3 is a schematic view showing the utilization of my novelcompressed air operating system as the primary operator for a circuitbreaker.

Figure 4 is a view in perspective of the type of circuit breaker used inFigure 1.

Figure 5 is a detailed vertical cross-section of the solenoid closingmechanism of the circuit breaker of Figure 4.

Figure 6 is a bottom View of the solenoid housing cover of Figure 5.

Referring lirst to Figure 1, I have here shown a tank I al having asupply of compressed air with an outlet pipe controlled by the handoperated valve E2. Pressure gauge I 'i indicates the operating pressureavailable for use in the hose I I. The tank Hi may be mounted in anysuitable manner for movement from breaker to breaker in the switchboardI3.

I have here shown one method of mounting the tank by means of anglebrackets I4 on cross bars iii which carry the wheels I6. The switchboardI3 comprises a plurality of circuit breaker compartments I8, I9, 2li,2|.

Compartment 2i houses a large truck mounted circuit breaker indicatedgenerally at 22 of the general type disclosed in application Serial No.757,356, iiled June 27, 1947, now Patent No. 2,611,838, and applicationSerial No. 720,561 led January 7, 1947, now Patent No. 2,601,417.Compartments I8, I9, and 2i) house smaller circuit breakers.

Compartments 23v and 24 may contain other apparatus necessary in aswitchboard as, for instance, a transformer or a switchgear.

Each of the circuit breakers in compartments I8, I9, 2li, and 2i isprovided with a pipe 25 which 1s preferably flexible and which isconnected from the circuit breaker to the coupling 25 mounted in thefront door of each of the respective compartments.

.The function of the preferably flexible pipe 25 will be hereinaftermore specically described.

The hose Il from the compressed air source I0 is provided with thematching coupling member 28 to interengage with coupling 26 of hose 25,

Assuming that each of the circuit breakers is operated to closedposition by a solenoid closing coil and assuming that one of thesolenoid closing coils is inoperative for any reason lwith the circuitbreaker open, then the portable compressed air supply I may be utilizedto reclose the circuit breaker without requiring that the operatorapproach the circuit breaker closing.

The operator moves the tank I0 to a position where the hose coupling 28of hose II may be connected to coupling 26 of pipe 25. After making thisconnection, he then returns to the tank |0 which may be located 'at aremote .point as determined by the length of hose and turns the valveoperator |2 to lead compressed air from the tank IIJ through pipes IIand 25 to the circuit breaker operating the circuit breaker to closedposition.

Should the, circuit breaker close on a short circuit, then the ope-raterbeing at a remote point operating the valve `|2wil1 be in a much saferposition than if he had attempted to close the circuit breaker manually.

The degree of safety will, of course, be determined by the length of theflexible hose which may be made long enough to provide absolute safetyunder all conditions.

As hereinafter pointed out, the utilization of the movable tank |6 andhose |I requires only minor modication of existing circuit breakerstructure; that is, it'would only be necessary to lengthen the guide4tube for the solenoid plunger to make -su're that the solenoid plungeris a piston-like fit in the guide tube, seal the bottoni of the gui-'detube leaving an opening to which the hose 25 may be connected and toconnect the hose 25 to the coupling 26 which may be connected to thedoor ofthe compartment.

This change injexisting solenoid operated circuit breakers requires aminimum of material and but an hou'r or two -of time. Consequently, theinstallation of the auxiliary compressed air yoperating system forutilization in `connection with many circuit breakers and even manyswitchboards requires 4only the single portable tank l0 and its hose andthe slight `change in each of the circuit breakers above mentioned `andhereinafter described.

While my invention, lof course, lends itself to permanent installations,the utilization of a portable tank and flexible hose II or at least theutilization of the detachable and attachabl'e construction of hose y||in connection with each of the hoses 25 is much simpler andl far moreeconomical than a plurality of parallel permanent 'compressed air pipelines.

In Figure 2 I have shown the modification that may readily be made Iacircuit breaker in rorder to enable my novel auxiliary compressed airsystem to operate.

The `circuit breaker is of the type disclosed in application serieu No.720,561, nled January 7, 194'?, now Patent No. '2,601,41'1, Aand is ofthe type described therein as a blow-open, blowelosed circuit breaker;that is, the closing movement andjust as the contacts engage, but beforethey have fully engaged, the current loop through the elements providesa'blow-closed effect, When the circuit breaker is tripped, the elementsare so arranged lthat the current loop provides a blow-open effect.

The circuit breaker ||0 `is supported Am any suitable manner on a panelIH, Carrying additional supporting brackets, not shown, to support thevarious pivot pins hereinafter described.

The back panel I I I carries an upper back connection stud H5 and alower back connection stud ||6, mounted in any suitable insulators 2 I5and 2I6. The upper back connection stud ||5 carries at the end thereof astationary contact structure Movable contact arm |25 carrylng movablecontact |26 and arc horn |21 is pivotally mounted on the pin |28 whichpasses through the arcuate horizontally extending slot |29 in extension|3| of the lower back connection stud H6.

Highly conductive inserts |34 on either side of the extension I3I ensuregood current conducting engagement between contact arm |25 and theextension I3I.

Arm |25 is a double arm, the elements of which are mounted on oppositesides of extension I3I and pressed by spring washers against conductiveinserts |34.

The current path established when the contacts' are closed is thus fromthe upper back connection stud ||5 to the stationary contact structure||1, then through movable Contact |26 and movable contact arm |25 totheextension 13| of the lower back connection stud ||6 and then to thelower back connection stud ||6.

It will thus be seen that when the contacts are closed, a U-shapedcurrent loop is established with the contact elements ||1|26 at yone ofthe bends or corners of the loop.

` The movable contact |25 is held closed during the 'operation of thecircuit breaker by the toggle |52, 'one link |53 of which is connectedto the pin |50 on contact arm |25, the opposite end Aof the link |53being Iconnected to the knee pin 4| 55 of the toggle |52.

The other link |54 of the toggle |52 is `connected at one end to theknee pin |55 and is pivoted at the other end on the stationary pin |51.Link |54 has 'a downward extension |62 which Awith link |54 forms a bellcrank lever IBI-|62. Roller l|63 secured at the end 'of link |62 isengaged in detent |64 'of latch |65.

When the overload trip kcoil |1| is energized, the armature |12 israised 'against 'extension l|61 of latch |65 causing the latch |65 topivot counterclockwis'e about 'the stationary pin |66 sothat the detent|64 thereof disengages roller |63 and the toggle |52 Amay break`downwardly to 'open the circuit 'breaker as shown in .Figure 2.

During the closing operation the 'possible movement of the toggle'upwardly through 'center is prevented bythe cross-bar or 'stop ITUabove the knee pin |55. When the toggle |52 has broken downwardly, thuspermitting the contact |25 to be forced open .by the blow-open eiect,the knee pin |55 drops and roller 63 rises. Roller V|63 is connected tothe link |15. Link |15 is provided at its outer left-hand end with.a-slot |16 in whichrides the vpin |11. Pin |11 is connected to theupper Iend of the bell crank liever latch |18 which is .fpivoted on thepin |19.

Latch |16 has a vdetent II-80 lwhich engages roller |8| on the closingfarm |82. rArm :|82 is .pivotally mounted -on the pin |63 and is biasedtoward the right into clockwise movement by the compression spring |84.

`When now the roller |63 rises up toward the left, on opening of thecontacts, the link 15 is driven tothe left rapidly and when the end |16aof the slot |16 strikes pin 111, latch v| 18 ,is given a hammer blow in'a -coun-terclockwise direction to disengage the detent from roller |8|.

;is pushed up,

the'compression spring 44 aids in maintaining the valve 4l against itsseat on the valve opening 40.

As the upper limit Yof travel of member 3c is reached, the collar 454 onvalve rod 42 strikes against the abutment 46 at the .bottom of member 30and the valve rod 42 and valve 4| are pulled upwardly opening theexhaust opening 40.

By this time, the toggle |90 has been extended to close the circuitbreaker or other closing apparatus has been operated to the full closedposition of the circuit breaker, and no further rise of the solenoidarmature-piston is needed and, of course, no further build-up oipressurein chamber :i4 is desired. Further building up of pressure is, however,avoided by the automatic opening of the valve 4l.

By this means, therefore, a simple modification of existing circuitbreaker construction makes possible the utilization of auxiliary remotecontrol air operating means for closing a circuit breaker withoutinterfering with the electrical operation thereof.

If, for any reason, the solenoid mechanism should go out of order, theoperator need not take the risk of manually closing the circuit breakeron a possible short circuit but need merely wheel the tank ||l to aposition where the hose may be attached to hose 25 and then standing tarenough from the circuit breaker to be safe he need merely voperate valveI2v to close the breaker.

If a short circuit does exist resulting in immediate reopening of thecircuit breaker with the attendant possibly dangerous arc, the operatoris suinciently remote from the circuit breaker and its compartment to besafe.

Where a single unit is to be available to operate many circuit breakers,it may even be desirable to fix the air tank and especially the valveoperator |2 at some position sufficiently remote from all circuitbreakers so that the operator turning the valve I2 at that position willbe absolutely safe, and then a hose il of sufficient length may beprovided so that it may be connected to any oi the circuit breakerswhich are to be operated by the auxiliary air system.

Such a stationary system for use in a large installation requires,however, its own air compressor and other auxiliary means for ensuring avcontinuous supply of air at full pressure. In a small sub-station, theadded cost of an air compressor may not be warranted, especially sincethe occasions when a solenoid coil will fail to operate will be veryrare.

Accordingly, the installation should be so arranged that it will not beexpensive. For this reason, a simple drum may be used for the tank l andit may be mounted in simple fashion on wheels or even a dolly to bereadily portable.

In a very small unit, the tank may even be filled by a hand pump or thetank may from time to time be taken down to a conveniently located powerpump to be refilled.

In Figure 3 I have shown a modification of. my invention so that it maybe utilized as the primary means for closing a circuit breaker ratherthan as an auxiliary means.

AIn this case, the solenoid coil |99 is dispensed with, and the guidetube 3| is the closing cylinder. Otherwise, all* of the elements operateas previously described in connection with Figure 2, but there is no.solenoid operated closing mechanism..

When it is desired to close the circuit breaker,

hose is connected to hose and air isadmitted to chamber 34a below thepiston 30a to operate the piston upwardly in the manner previouslydescribed. All other elements of the air system as weli as of thecircuit breaker may be identical.

While in the circuit breaker here disclosed I have not shown manualclosing means, it will be obvious that a handle attached to link |91 or"toggle la may be utilized to close the circuit breaker manually for testpurposes but since the possibility that short circuit may exist stillremains when the circuit breaker is in the operative position, theauxiliary air system here disclosed may be utilized with absolute safetyby the operator I to close the circuit breaker even on a short circuit.

In Figure 4 I have shown in perspective a standard circuit breaker 22 ofthe type shown in Figure l and well-known in the art, the circuitbreaker being provided with the solenoid housing 5l) shown in greaterdetail in Figures 5 and 6. The solenoid mechanism in housing 50 acts asthe operating means for closing the circuit breaker.

Solenoid core 5ft acts as a piston, travelling from the dotted lineposition 55 to the solid line position 5S to drive the plunger 52upwardly to close the circuit breaker. rhe solenoid coil normally drivesthe core 54 upwardly. When it is desired to utilize iiuid pressure todrive core Fifi upwardly to close the circuit breaker, pipe 25 isattached to the tapped opening 53 in solenoid housing cover 5d to admitiiuid under pressure below the core 5d. The operation for closing thecircuit breaker is then identical' with that described in connectionwith Figures i to 3.

While in the foregoing I nave disclosed a specie type oi circuit breakerin which a toggle is extended to close the contacts, it will be obviousthat this system is applicable as well to all other types of circuitbreakers.

The system of Figure 2 may be utilized in ccnnection with any solenoidoperated circuit breaker, and the system of Figure 3 may be utilized inconnection with any type of circuit breaker whether manually or solenoidoperated.

The circuit breakers in connection with which my invention is used mayhave manual closing means, solenoid closing means or even special airoperated closing means. My auxiliary air operating system may be utifcedin connection with any of these closing means or a substitute thereforwhere closing the circuit breaker manually is dangerous, where theclosing solenoid is out of order for any'reason, or where the normal airoperated closing system is out of order for any reason.

In the foregoing I have described my invention solely in connection withspecific illustrative embodiments thereof, Since many variations andmodifications of my invention will now be obvious to those skilled inthe art, I prefer to be bound not by the specific disclosures hereincontained but only by the appended claims.

I claim:

l. In a circuit breaker having a pair of cooperable contacts, anelectromagnet having an armature, mechanism controlled by said armaturefor operating said contacts into engagement,.a chamber for saidarmature, said armature forming a piston in said chamber, and a sourceof iiuid pressure connectable to said chamber for operating saidcontacts into engagement.

2. In a switchboard, a plurality of circuitV breakers, a compartmentindividual to each of said circuit breakers, each'of said circuit break-The compression spring |84 is now in a position to drive the arm |82clockwise around the pivot |83. This results in the movement of theparts to the condition wherein the closing toggle I9l has collapsed andin which the adjustable stop member |9| at the upper end of the arm |82strikes the extension |52 or the link |4 rotating link |54-I62 in acounterclockwise direction to reextend the toggle |52 once more and tore* engage the roller I3 in detent lifi of latch |65.

The re-setting or extending of the toggle |52 does not at this time,however, result in closing of the circuit breaker, since pin |85 on arm|82 which is connected to arm |62 moves the arm I6I to the right, thusmoving the pin it@ at the lower end of contact arm |25 to the right.This moves the pin |25 of the contact arm |25 to the right-hand side ofthe slot |29 but at the same time pushes the pin |55 over suiiicientlyso that the contact arm continues to rotate outwardly toward the leftaround pin |28 which is held by the right-hand end of slot |29. Thus,even though the latch |535 is re-set, the circuit breaker remains open.

The closing toggle i B is prevented from breaking upwardly by the stop|95. Toggle |90 comprises a link |93 connected by pin |94 to the closingarm |82 and connected at the other end to the knee pin |56. Link lill isconnected at one end to knee pin |95 and at the other end to thestationary pin |98. Closing solenoid ISES is provided with the armature20d.

Now when the circuit breaker is in the open position with the latchesall re-set, the contacts may be closed by energization or" the solenoidcoil |99. On such energization the armature 2th? is raised to extend thetoggle Hill. When the toggle I 90 is thus extended, closing arm |52 isrotated counterclockwise to the left about pin |83. This compresses thespring |84 and moves the arm 82 over to the left until latch |13 engagesroller IBI on the arm IM. At the same time the movement of arm I 82 tothe left `pulls the arm |6| to the left, thus pulling on pin Idil andcausing the contact arm |25 to rotate in a counterclockwise directionaround the pivot pin I.

Spring |54 is provided only to re-set, the toggle |52 and consequentlyis a relatively light spring so that it does not interfere with theclosing of contacts as would be the case where opening springs are used.Thus, the mechanical force needed to close the contact is only necessaryto overcome the inertia of the parts and the relattively slight force ofthe re-setting spring |84.

The contacts are driven home once they are initially engaged by theblow-closed effect above described. In fact, the closing coil andarmature, as hereinafter pointed out, are aided by the arrangement ofthe parts which produce a net blow-closed effect during closing.

Also, the travel which is given to the closing coil and plunger 2D!)need merely be suilicient to complete the closing operation and noover-travel need be provided to provide any hammer blow or kineticeiiect to slam the contacts home. The parts may thus be made lighter andat the same time, owing to the utilization of the electromagnetic forcesto close the contacts rather than sheer mechanical force or kineticenergy, the parts are more durable.

Thus far, one type of circuit breaker in connection with which myinvention may operate has been described. rihis circuit breaker has beendescribed specifically so that a complete operative system may be shown,

' It will be obvious, however, from the following that any circuitbreaker with a solenoid closing coil may readily be adapted to utilizethe principles of my invention and, in fact, any. circuit `breaker maybe operated Whether or not it has a solenoid closing coil in accordancewith the principles oi my invention.

Referring again to Figure 2, the closing plunger 200 is, as waspreviously pointed out, operated by the armature 3|) or" the solenoidcoil |99. The armature 3G operates in the guide tube 3|.

In accordance with my invention, the guide tube 3| which is normallyonly slightly longer than the coil IQS is extended downwardly to form acylinder. The bottom of the guide tube is sealed by wall 32. The pipe orilexible hose 25 is connected to opening 33 in the bottom Wall 32 sothat air may be admitted to the chamber 34 oi the guide tube 3| belowthe armature 30 which is a piston-like iit in the guide tube 3 I.

When air is thus admitted, as previously described, from tank IO throughhose I|, couplings 28 and 26, pipe 25, and opening 33 to chamber 34,compressed air forces the armature 30 which now acts as a piston toforce the plunger 20E) up, extending the toggle and closing the circuitbreaker.

This is the only modincation that is essential in order to adapt thecircuit breaker to the utilization of my novel auxiliary system.

After the circuit breaker is closed. however, the various latchesabove-described hold it closed and it is no longer necessary to supportthe armaturepiston 30 by air or other means.

It may in certain circumstances be desirable, in fact, to lead oi theair in chamber 34 to prevent excess pressure in the guide tube 3|. Thatis, in order to utilize the tank for many operations Without thenecessity for recharging it frequently, it may be desirable to chargethe tank I0 to a pressure much higher than that which is necessaryactually to close a particular circuit breaker.

When the valve I2 is opened, the pressure builds up quickly in chamber34 of the guide tube to force the piston-armature 30 up as the pressureincreases. After the armature 30 has been forced up to close the circuitbreaker, no further build-up of pressure is needed or even desired.

Hence, it is desirable to provide an exhaust valve in the guide tube 3|so that pressure will not build up too high therein. rI'he operator whoturns the valve can thus watch the appropriate indicator on theswitchboard and when it hasy shifted from open to "closed, then he needmerely close the valve I 2.

Where an exhaust valve is provided in the guide tube, then lowerpressures must be used in guide tube is needed, or the operator must bevery skillful and quick in operating the valve |2U to close the same themoment the circuit breaker As the armature-piston 3|);

ers having a pair of cooperable contacts, an electromagnet having anarmature, mechanism controlled by said armature for operating saidcontacts into engagement by either electrical or hydraulic influence, achamber for said armature, said armature forming a piston in saidchamber.

3. In a switchboard, a plurality of circuit breakers, a compartmentindividual to each of said circuit breakers, each of said circuitbreakers having a pair of cooperable contacts, an electromagnet havingan armature, mechanism controlled by said armature for operating saidcontacts into engagement, a chamber for said armature, said armatureforming a piston in said chamber, a portable source of iuid pressureconnectable to said chamber for operating said contacts into engagement,and means :for selectively making said connection from said source toany one of said circuit breaker mechanisms.

4. In a circuit breaker having a pair of cooperable contacts, anelectromagnet having an armature, mechanism controlled by said armaturefor operating said contacts into engagement, a cham- 10 ber for saidarmature, said armature forming a piston in said chamber, a source offluid pressure connectable to said chamber for operating said contactsinto engagement, a normally closed eX- haust vent, and means operated assaid contacts are operated into engagement for opening said vent to dropthe pressure in said chamber.

JOSEPH D. WOOD.

References Cited in the file of this patent UNITED STATES PATENTS

